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71.
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73.
对荷兰花卉产业的现状及其主要的经验作了介绍, 并就云南省花卉产业发展的利弊作出评述。借鉴荷兰花卉业发展的成功经验, 结合云南的实际, 提出了9条发展云南花卉产业的建议。 相似文献
74.
中国综合花卉市场营销策略研究 总被引:5,自引:0,他引:5
花卉市场作为花卉产品的集散中心,给花卉业的建设和发展带来了新的生机和活力,大大促进了花卉产业化的形成和发展。文章采用典型调查、动态研究、比较研究的方法,研究分析了我国花卉市场营销的发展现状、存在的问题,并提出了中国现阶段综合性花卉市场的定位、选址、规模、管理模式、经营特色、市场行为规范、售后服务、宣传方式、打造特色品牌、设施建设等方面的营销策略,以期望能够对中国综合性花卉市场建设具有指导意义。 相似文献
75.
影响鹤望兰切花产量与质量的因素探讨 总被引:1,自引:0,他引:1
探讨夏季遮荫、冬季保温、喷雾、修剪等因素对鹤望兰切花产量与质量的影响,结果表明:夏季遮荫对切花产量与一级花率影响不显著,但比对照二、三级花率提高28.6%;冬季保温栽培能显著提高12月—翌年3月切花产量,比露地栽培提高182.4%,二、三级花率也提高19.1%;对大于25株/丛、10a龄的植株采用留10~19株的修剪方式全年产量比对照降低了15.1%,但能显著提高切花质量,一级花率比对照提高105.2%;采用修剪结合夏季遮荫、冬季保温、喷雾等处理措施既能提高鹤望兰切花年产花量,比修剪后露地栽培提高30.0%,也能提高切花质量,其中一级花率提高37.3%。 相似文献
76.
探索罗汉果花提取液对亚硝酸盐的清除效果,为罗汉果花的开发利用提供相关理论依据。以罗汉果花提取液对亚硝酸盐的清除率为考察指标,分别研究不同提取方法和提取溶剂所获得的提取液对亚硝酸盐的清除效果,在确定最佳提取方法和提取溶剂的基础上,通过单因素试验和正交试验对提取工艺进行优化。结果表明,采用蒸馏水作为溶剂,利用微波辅助浸提法效果较好,最佳提取工艺为:微波功率490 W,提取时间2 min,料液比1∶15(g/mL)。在此条件下,罗汉果花提取液对亚硝酸盐清除率达到56.83%。 相似文献
77.
不同叶龄蘖、穗氮肥组合对粳稻产量及氮素利用的影响 总被引:4,自引:0,他引:4
以主茎叶片数不同的粳稻品种吉粳88 (14片)、沈农265 (15片)和沈农1401 (16片)为试材,采用大田筒栽方式,在总施氮量225kghm–2及轻简施肥(基肥、蘖肥、穗肥)模式基础上,设置基蘖肥∶穗肥6∶4和8∶2两种施肥比例,并分设不同源、库叶龄期施氮组合即不同叶龄蘖、穗肥精确施氮组合。分析了不同源库期氮肥运筹模式对水稻农艺性状、产量及氮素利用特性的影响。结果表明:(1)在有效穗数、分化颖花数、产量和氮素利用率方面,吉粳88、沈农265、沈农1401不同氮肥运筹下最佳蘖、穗肥叶龄组合均为6∶4显著高于8∶2。(2)不同氮肥运筹下,吉粳88在8叶(叶龄指数57.1%)、沈农265在9叶(叶龄指数60.0%)、沈农1401在10叶(叶龄指数62.5%)时,即叶龄指数在60%左右时,施用蘖肥效果最佳,最终穗数最多,对保蘖起主要作用;吉粳88在11叶(叶龄指数78.6%)、沈农265在12叶(叶龄指数80.0%)、沈农1401在13叶(叶龄指数81.3%)时,即叶龄指数在80%左右时,施用穗肥效果最佳,最终穗粒数最多,对促花起主要作用。(3)吉粳88-6∶4 (8, 11),沈农26... 相似文献
78.
Bolting and flowering of Aster novi-belgii seedlings as well as correlations between characteristics within seedling populations
and between seedlings and their vegetatively propagated offspring were investigated in order to improve breeding efficiency.
In seedlings of A. novi-belgii, flower induction was observed without vernalization. Seedlings initially formed a rosette,
but bolting was a prerequisite for development of a normal flowering shoot. Bolting was promoted by long photoperiods as compared
to short days. The shortest time from sowing to anthesis was recorded when plants were grown under long photoperiods until
the main stem was at least 5 cm long, and then moved to short photoperiods. A large variation in time to anthesis, plant height,
branching ability, and flower size and color was found among the seedlings within all crosses. Magnitude and significance
of correlations between some characteristics varied among crosses. The more consistent correlations seem mainly to be due
to natural courses of plant growth and development. High correlations between seedling characteristics and their vegetatively
propagated offspring were only found for flower hue. Lower, but significant correlations were found for flower color intensity,
plant height and branching ability. There were no significant correlations for the time-to-anthesis between the two groups
of plants.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
79.
Meghnath Pokharel Anuj Chiluwal Michael Stamm Doohong Min Davina Rhodes S.V. Krishna Jagadish 《Journal of Agronomy and Crop Science》2020,206(5):579-596
Winter canola (Brassica napus L.) is highly sensitive to increasing temperatures during the reproductive and pod-filling stages. Although the impact of high day-time temperature stress on yield and quality has been documented in canola, similar information under high night-time temperature (HNT) stress is not available. Using six hybrids and four open-pollinated cultivars, we observed a marked shift in peak flowering towards earlier, cooler hours of the morning under HNT. Averaged across two independent experiments, the photochemical efficiency of photosystem II was significantly decreased (3%), with a significant increase in thylakoid membrane damage (13%) in the leaves of susceptible cultivars under HNT stress. Similarly, the susceptible cultivars also recorded significant reduction in biomass (34%), pod number (22%), pod weight (37%) and total seed weight (40%) per plant while the same set of agronomic traits were not affected among the tolerant cultivars. Quantitative impact of heat stress was confirmed with increased sensitivity to HNT exposure from gametogenesis until maturity resulting in a significantly higher yield loss compared to stress exposure from post-flowering till maturity. HNT significantly decreased oil concentration, but increased protein concentration and saturated fatty acid levels in seeds of the susceptible cultivars. However, HNT had no impact on the unsaturated fatty acids in both hybrids and the open-pollinated cultivars. Breeding targets based on fatty acid composition for enhancing canola seed quality may not be easily amenable due to the inconsistency documented with the compositional changes under heat stress. In summary, our findings conclude that canola hybrids are better suited to regions experiencing heat stress, compared to open-pollinated cultivars, indicating the possibility of a complete shift to hybrid canola cultivation under predicted hotter climates in the future. 相似文献
80.